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Venus, lacking an intrinsic global dipole magnetic field, serves as a textbook example of an induced magnetosphere, formed by interplanetary magnetic fields (IMF) enveloping the planet. Yet, various aspects of its magnetospheric dynamics and planetary ion outflows are complex and not well understood. Here we analyze plasma and magnetic field data acquired during the fourth Venus flyby of the Parker Solar Probe (PSP) mission and show evidence for closed topology in the nightside and downstream portion of the Venus magnetosphere (i.e., the magnetotail). The formation of the closed topology involves magnetic reconnection-a process rarely observed at non-magnetized planets. In addition, our study provides an evidence linking the cold Venusian ion flow in the magnetotail directly to magnetic connectivity to the ionosphere, akin to observations at Mars. These findings not only help the understanding of the complex ion flow patterns at Venus but also suggest that magnetic topology is one piece of key information for resolving ion escape mechanisms and thus the atmospheric evolution across various planetary environments and exoplanets.

In industrial vision metrology, precise spatial measurement is vital for quality control and complex manufacturing, traditionally relying on target arrays for sub-pixel accuracy (0.05–0.1 pixels) and precision to beyond 1:200,000. However, target design, placement and measurement are often time-consuming and challenging for large-scale projects. Automated, markerless methods, generally called Structure-from-Motion (SfM), based on handcrafted algorithms or deep learning-based pipelines, offer greater flexibility but are not widely adopted due not only to concerns about reliability and precision, but also because in many industrial photogrammetry applications targets highlight particular feature points of interest, e.g. tooling points, holes and edges. This study reviews the differences between target-, handcrafted- and learning-based approaches, explores hybrid methods combining targets and natural features, and tests learning-based or handcrafted approaches against the traditional target-based method. Two end-to-end learning-based pipelines based on SuperPoint+LightGlue and KeyNet+AffNet+HardNet are evaluated. Results show that deep learning pipelines for tie point extraction provide enhanced automation but inferior triangulation precision, while being comparable to handcrafted methods.

Knee arthroplasty benefits significantly from computer-assisted navigation, which improves the accuracy of prosthesis placement. However, current methods require invasive optical locators to track the position of the knee, which carries risks such as infection and prolonged healing times. To address these limitations, this work uses markerless trinocular SLAM to achieve accurate 3D reconstruction of the knee during surgery. The approach integrates SuperGlue for robust feature matching and incorporates segmentation to mask the knee, improving reconstruction accuracy despite challenges such as low-texture surfaces, reflections and spotlight illumination. The accuracy of the handheld trinocular camera system is evaluated under dynamic conditions, simulating camera movement during surgery to ensure accurate reconstruction during real-time surgery. In addition, a robot-guided dataset will be used to assess the repeatability and robustness of the SLAM approach. This research focuses on positional accuracy in motion and aims to advance real-time, non-invasive navigation solutions for knee arthroplasty, contributing to safer and more efficient surgical outcomes.

Abstract: The anisotropy of energetic particles provides essential information to help resolve the underlying fundamental physics of their spatial distributions, injection, acceleration, and transport processes. In this work, we report an energetic ion enhancement that is characterized by very large and long-lasting anisotropies observed by STEREO A and Solar Orbiter, which are nearly aligned along the same nominal Parker spiral. This ion enhancement appears at the rising phase of a widespread solar energetic particle event that was associated with the farside coronal mass ejection on 2022 February 15. According to our analysis, the long-lasting anisotropy resulted from the continuous injection of energetic ions from a well-connected particle source located beyond the STEREO A’s orbit. Solar Orbiter also observed an interval of very large anisotropy dominated exclusively by sunward streaming ions but with the additional implication that it detected the very early phase of ion injections onto magnetic field lines that newly connected to the particle source, which is likely the first reported event of this kind. These results further illustrate how energetic particle anisotropy information, in particular from multiple observer locations, can be used to disentangle the sources and transport processes of energetic ions, even when their heliospheric context is not simple.

What does a social learner learn? Research has explored imitation-based social learning strategies as well as inverse reinforcement algorithms that estimate others' true reward function. In the current study, we propose that social learning may be more elaborate and develop a model of social learning using Bayesian inference that seeks to understand both the task an observed demonstrator is performing and the demonstrator itself. Using simulations, we show that the model is able to learn about the demonstrator when provided with full and partial information. We strengthen this point by asking the model to make inferences about missing choice and reward information. Last, we show that the model is able to represent one set of beliefs about the environment while attributing a distinct set of beliefs to the demonstrator. Thus, we move away from simple models of social learning, investigating inference-making as a core mechanism of social learning.

BackgroundMeasuring the incidence of HIV and hepatitis C virus (HCV) infection among people who inject drugs (PWID) is key to track progress towards elimination. We aimed to summarise global data on HIV and primary HCV incidence among PWID and associations with age and sex or gender.MethodsIn this systematic review and meta-analysis, we updated an existing database of HIV and HCV incidence studies among PWID by searching MEDLINE, Embase, and PsycINFO, capturing studies published between Jan 1, 2000, and Dec 12, 2022, with no language or study design restrictions. We contacted authors of identified studies for unpublished or updated data. We included studies that estimated incidence by longitudinally re-testing people at risk of infection or by using assays for recent infection. We pooled incidence and relative risk (RR; young [generally defined as ≤25 years] vs older PWID; women vs men) estimates using random-effects meta-analysis and assessed risk of bias with a modified Newcastle-Ottawa scale. This study is registered with PROSPERO, CRD42020220884.FindingsOur updated search identified 9493 publications, of which 211 were eligible for full-text review. An additional 377 full-text records from our existing database and five records identified through cross-referencing were assessed. Including 28 unpublished records, 125 records met the inclusion criteria. We identified 64 estimates of HIV incidence (30 from high-income countries [HICs] and 34 from low-income or middle-income countries [LMICs]) and 66 estimates of HCV incidence (52 from HICs and 14 from LMICs). 41 (64%) of 64 HIV and 42 (64%) of 66 HCV estimates were from single cities rather than being multi-city or nationwide. Estimates were measured over 1987-2021 for HIV and 1992-2021 for HCV. Pooled HIV incidence was 1·7 per 100 person-years (95% CI 1·3-2·3; I2=98·4%) and pooled HCV incidence was 12·1 per 100 person-years (10·0-14·6; I2=97·2%). Young PWID had a greater risk of HIV (RR 1·5, 95% CI 1·2-1·8; I2=66·9%) and HCV (1·5, 1·3-1·8; I2=70·6%) acquisition than older PWID. Women had a greater risk of HIV (RR 1·4, 95% CI 1·1-1·6; I2=55·3%) and HCV (1·2, 1·1-1·3; I2=43·3%) acquisition than men. For both HIV and HCV, the median risk-of-bias score was 6 (IQR 6-7), indicating moderate risk.InterpretationAlthough sparse, available HIV and HCV incidence estimates offer insights into global levels of HIV and HCV transmission among PWID. Intensified efforts are needed to keep track of the HIV and HCV epidemics among PWID and to expand access to age-appropriate and gender-appropriate prevention services that serve young PWID and women who inject drugs.FundingCanadian Institutes of Health Research, Fonds de recherche du Québec-Santé, Canadian Network on Hepatitis C, UK National Institute for Health and Care Research, and WHO.

PurposeBrace treatment is the most common nonoperative treatment to prevent curve progression in adolescent idiopathic scoliosis (AIS). The goal of this review and analysis is to characterize curve behavior after completion of brace treatment and to identify factors that may facilitate the estimation of long-term curve progression.MethodA review of the English language literature was completed using the MEDLINE (PUBMED) database of publications after 1990 until September 2020. Studies were included if they detailed a minimum of 1 year post-brace removal follow-up of AIS patients. Data retrieved from the articles included Cobb angle measurements of the major curves at "in-brace," weaning, and follow-up visit(s) for all patients described and for subset populations.ResultsFrom 75 articles, 18 relevant studies describing a follow-up period of 1-25 years following brace removal were included in the analyses. The reviewed literature demonstrates that curves continue to progress after brace treatment is completed with three main phases of progression: (i) immediate (upon brace removal) where a mean curve progression of 7° occurs; (ii) short term (within five years of brace removal) where a relatively high progression rate is evident (0.8°/year); and (iii) long term (more than five years after brace removal) where the progression rate slows (0.2°/year). The magnitude and rate of curve progression is mainly dependent on the degree of curve at weaning as curves weaned at

In uncertain environments, individuals often use external cues to guide their judgments and decisions. Anchoring refers to the finding that numerical judgments often gravitate towards previously considered standards. Although an extremely robust effect, prior research on anchoring largely focused on single-anchor paradigms. The present study instead investigated how multiple anchors affect numerical judgments. In Experiment 1, participants exposed to both a low and high anchor provided judgments that were between judgments made by participants exposed solely to low or high anchors. However, anchors that were encountered first exerted a disproportionate influence on subsequent judgments. Experiment 2 replicated this primacy effect both when anchors were plausible or implausible standards. Finally, Experiment 3 demonstrated that this primacy effect was reduced to non-significance by inserting a secondary distraction task following the exposure to each anchor. Implications of the current multiple-anchor results for various theories of anchoring effects are discussed.

The exploration-exploitation dilemma in dynamic decision-making scenarios is a notoriously hard problem to solve. Having a partner to potentially learn from might make it easier to balance exploration and exploitation. In the current study, we investigate the impact of social information (i.e., about others’ exploration behavior vs. their rewards) and partner performance (optimal vs. random) on participants’ behavior in a dynamic decision-making task that contains a learning trap. We find that observing the exploration behavior of an optimally choosing partner was detrimental to participants’ overall performance and reduced participants’ exploratory tendencies. In contrast, observing a random partner’s exploration behavior stimulated participants’ exploration, though this increase in exploration did not help participants to uncover the reward function. Following previous literature, a reinforcement learning model that contained eligibility traces was able to describe human behavior and helped to uncover potential mechanisms that could explain aspects of the findings.

Traditionally, heliophysics is characterized as the study of the near-Earth space environment, where plasmas and neutral gases originating from the Earth, the Sun, and other solar system bodies interact in ways that are detectable only through in-situ or close-range (usually within ∼10 AU) remote sensing. As a result, heliophysics has data from the space environment around a handful of solar system objects, in particular the Sun and Earth. Comparatively, astrophysics has data from an extensive array of objects, but is more limited in temporal, spatial, and wavelength information from any individual object. Thus, our understanding of planetary space environments as a complex, multi-dimensional network of specific interacting systems may in the past have seemed to have little to do with the highly diverse space environments detected through astrophysical methods. Recent technological advances have begun to bridge this divide. Exoplanetary studies are opening up avenues to study planetary environments beyond our solar system, with missions like Kepler, TESS, and JWST, along with increasing capabilities of ground-based observations. At the same time, heliophysics studies are pushing beyond the boundaries of our heliosphere with Voyager, IBEX, and the future IMAP mission. The interdisciplinary field of star-exoplanet interactions is a critical, growing area of study that enriches heliophysics. A multidisciplinary approach to heliophysics enables us to better understand universal processes that operate in diverse environments, as well as the evolution of our solar system and extreme space weather. The expertise, data, theory, and modeling tools developed by heliophysicists are crucial in understanding the space environments of exoplanets, their host stars, and their potential habitability. The mutual benefit that heliophysics and exoplanetary studies offer each other depends on strong, continuing solar system-focused and Earth-focused heliophysics studies. The heliophysics discipline requires new targeted funding to support inter-divisional opportunities, including small multi-disciplinary research projects, large collaborative research teams, and observations targeting the heliophysics of planetary and exoplanet systems. Here we discuss areas of heliophysics-relevant exoplanetary research, observational opportunities and challenges, and ways to promote the inclusion of heliophysics within the wider exoplanetary community.

The Martian magnetotail exhibits a highly twisted configuration, shifting in response to changes in polarity of the interplanetary magnetic fields (IMF) dawn-dusk (B Y) component. Here, we analyze ∼6000 MAVEN orbits to quantify the degree of magnetotail twisting (θ Twist) and assess variations as a function of (a) strong planetary crustal field location, (b) Mars season, and (c) downtail distance. The results demonstrate that θ Twist is larger for a duskward (+B Y) IMF orientation a majority of the time. This preference is likely due to the local orientation of crustal magnetic fields across the surface of Mars, where a +B Y IMF orientation presents ideal conditions for magnetic reconnection to occur. Additionally, we observe an increase in θ Twist with downtail distance, similar to Earths magnetotail. These findings suggest that coupling between the IMF and moderate-to-weak crustal field regions may play a major role in determining the magnetospheric structure at Mars.

To better understand the effects of life events, research interest recently turned to the question of how life events are perceived (e.g., as positive, predictable, or controllable). However, research on this topic primarily focused on young adulthood, leaving it unclear whether and how the perception of life events varies across the life course. In this study, we examined the relationship between age and different perceived event characteristics using nationally representative data from the German Socioeconomic Panel Innovation Sample (N = 1,044). We found that people reported different event types across among age groups. Furthermore, the perception of life events varied across age and depending on whether an event was experienced at a normative age or not. These findings underline the necessity to take on a life-course perspective when examining life events and support theoretical claims on the relevance of age norms in life-event research.

McCrae (2020) argues that it is premature to explore interventions focused on personality change. In his commentary, he suggests that interventions should be promoted only if their effects in self-report data are confirmed by the additional opinion of informants. We agree with the essence of his position and would go further by envisioning a new framework for rigorous collaborative research on personality change (Bleidorn et al., 2020). We nevertheless maintain that policymakers would benefit from considering the additional opinion of personality scientists. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

The importance of personality for predicting life outcomes in the domains of love, work, and health is well established, as is evidence that personality traits, while relatively stable, can change. However, little is known about the sources and processes that drive changes in personality traits and how such changes might impact important life outcomes. In this paper, we make the case that the research paradigms and methodological approaches commonly used in personality psychology need to be revised to advance our understanding of the sources and processes of personality change. We propose Longitudinal Experience-Wide Association Studies as a framework for studying personality change that can address the limitations of current methods, and we discuss strategies for overcoming some of the challenges associated with Longitudinal Experience-Wide Association Studies. © 2020 European Association of Personality Psychology.

This article is an English translation of Niklas Luhmann's essay, "Erziehung als Formung des Lebenslaufes." Any review of what takes place nowadays in the "education system" soon reveals that no account, let alone theory, covers everything to be found there. It embraces not only schools and universities but also kindergartens and institutes of adult education, further education courses and "educational travel," vocational training and general education. The issue of the unity and the specific modus operandi of the system can be raised with respect to various distinctions, for example that between general and occupational education, but would scarcely extend to kindergartens and driving schools. In this essay, Luhmann focuses on another volatile difference, that between children and adults. [This article was translated by Rhodes Barrett.]

Image-based 3D reconstruction has been successfully employed for micro-measurements and industrial quality control purposes. However, obtaining a highly-detailed and reliable 3D reconstruction and inspection of non-collaborative surfaces is still an open issue. Photometric stereo (PS) offers the high spatial frequencies of the surface, but the low frequency is erroneous due to the mathematical model's assumptions and simplifications on how light interacts with the object surface. Photogrammetry, on the other hand, gives precise low-frequency information but fails to utilize high frequencies. As a result, in this research, we present a fusion strategy in Fourier domain to replace the low spatial frequencies of PS with the corresponding photogrammetric frequencies in order to have correct low frequencies while maintaining high frequencies from PS. The proposed method was tested on three different objects. Different cloud-to-cloud comparisons were provided between reference data and the 3D points derived from the proposed method to evaluate high and low frequency information. The obtained 3D findings demonstrated how the proposed methodology generates a high-detail 3D reconstruction of the surface topography (below 20 µm) while maintaining low-frequency information (0.09 µm on average for three different testing objects) by fusing photogrammetric and PS depth data with the proposed FFT-based method.

The verification of a measurement system is an essential part of system development. For this purpose, various guidelines can be used to evaluate and validate photogrammetric systems. However, these guidelines are only designed to validate systems that observe a static scene. Hence, these guidelines cannot validate measurement systems that observe dynamic scenes. In addition, reference data is not available for most systems, making verification significantly more difficult or not a practical solution. In this work, a simulation-based verification approach is presented. The presented approach allows the analysis of complex systems and the investigation of specific processing steps. The approach is based on a Monte Carlo simulation, which only requires the probability density distributions of the input data and synthetic reference data. For this purpose, the probability density distributions of the input data are determined by kernel density estimation to generate realistic input data. The application is a wind tunnel test, where aerodynamic and structural dynamic phenomena are observed at a wind turbine model. The measurement system consists of four high-speed cameras, which acquire the rotor blades' deformations. The objective of the simulation is to evaluate the complete process regarding the accuracy and precision of the measurement system. Experimental data can be used to estimate the quality of the simulation. It was shown that the simulation produces realistic results and that it is suitable for validating dynamic measurement systems. The simulation showed that the precision and accuracy of the system are highly dependent from the estimation of the self-motion. The achieved accuracy is still high and allows the detection of small-scale blade deformations.

Multimedia camera calibration is a challenging, yet increasingly important task. Due to the lack of software with appropriate models, implicit calibrations with standard single-media models are often performed, despite the well-known fact that distance-dependent errors arise from neglecting the specific multimedia influences. This becomes particularly relevant when test field calibrations are employed. We present a thorough simulation approach that shows the influence of distance-dependent errors when performing implicit calibration. Results show major accuracy decreases for performing measurements far from the calibration distance while closer distances may compensate the errors quite well. Furthermore, we investigate on the behavior of different test field geometries and angles between interface and optical axis which particularly affects the achievable accuracy.

Abstract Inhibitory interneurons play central roles in the modulation of spontaneous network activity and in processing of neuronal information. In sensory neocortical areas, parvalbumin-positive (PV+) GABAergic interneurons control the representation and processing of peripheral sensory inputs. We studied the functional role of PV+ interneurons in the barrel cortex of anesthetized adult PVCre mice by combining extracellular multi-electrode recordings with optogenetic silencing of a small fraction of PV+ interneurons. In all cortical layers, optogenetic inhibition caused an increase in spontaneous network activity from theta to gamma frequencies. The spatio-temporal representation of sensory inputs was studied by stimulating one or two whiskers at different intervals and analyzing the resulting local field potential (LFP) and single unit (SU) response. Silencing PV+ interneurons caused an increase in LFP response to sensory stimulation and a decrease in temporal discrimination of consecutive whisker deflections. The combined effect of whisker deflection and optogenetic inhibition was highly similar to the linear sum of the individual effects of these two manipulations. SU recordings revealed that optogenetic silencing reduced stimulus detectability by increasing stimulus-evoked firing rate by a constant offset, suggesting that PV+ interneurons improve signal-to-noise ratio by reducing ongoing spiking activity, thereby sharpening the spatio-temporal representation of sensory stimuli.